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Wildfire refugia (unburnt patches within large wildfires) are important for the persistence of fire‐sensitive species across forested landscapes globally. A key challenge is to identify the factors that determine the distribution of fire refugia across space and time. In particular, determining the relative influence of climatic and landscape factors is important in order to understand likely changes in the distribution of wildfire refugia under future climates. Here, we examine the relative effect of weather (i.e. fire weather, drought severity) and landscape features (i.e. topography, fuel age, vegetation type) on the occurrence of fire refugia across 26 large wildfires in south‐eastern Australia. Fire weather and drought severity were the primary drivers of the occurrence of fire refugia, moderating the effect of landscape attributes. Unburnt patches rarely occurred under 'severe' fire weather, irrespective of drought severity, topography, fuels or vegetation community. The influence of drought severity and landscape factors played out most strongly under 'moderate' fire weather. In mesic forests, fire refugia were linked to variables that affect fuel moisture, whereby the occurrence of unburnt patches decreased with increasing drought conditions and were associated with more mesic topographic locations (i.e. gullies, pole‐facing aspects) and vegetation communities (i.e. closed‐forest). In dry forest, the occurrence of refugia was responsive to fuel age, being associated with recently burnt areas (<5 years since fire). Overall, these results show that increased severity of fire weather and increased drought conditions, both predicted under future climate scenarios, are likely to lead to a reduction of wildfire refugia across forests of southern Australia. Protection of topographic areas able to provide long‐term fire refugia will be an important step towards maintaining the ecological integrity of forests under future climate change. [ABSTRACT FROM AUTHOR]

Megafires, predicted to become more frequent with a changing climate, pose a global challenge for conservation. Initial assessments of the 2019/20 megafires of Australia's 'Black Summer' highlighted widespread, severe impacts for many species. Post-fire empirical investigations are critical to evaluate the distribution and conservation status of species. We investigated the impacts of megafire on the southern superb lyrebird (Menura novaehollandiae victoriae), a functionally important ecosystem engineer in forest ecosystems. We quantified the extent of lyrebird habitat burned at differing levels of severity, and how this varied among forest types. One-year post-fire, we carried out field surveys at 226 sites, stratified by forest type and fire severity, to assess the impact on lyrebirds. In total, 41.5 % (~2.1 million ha) of habitat was burned at differing levels of severity. Habitats of higher predicted quality were disproportionately affected. At one-year post-fire, lyrebirds were strongly affected by fire severity: their occurrence, as indicated by foraging activity, was greatly reduced in forests burned at high and low severity, but patchily burned forest differed little from unburned forest. Notably, foraging was almost completely absent from all sites that experienced high severity fire, except in rainforest. Rainforests (<1 % of distribution) have the greatest post-fire value for lyrebirds; they serve as local refuges for recolonization and are a priority for restoration efforts. Importantly, impacts of megafires are not uniform but vary greatly in relation to fire severity and forest type. Such knowledge is essential for long-term conservation of species of concern, including the identification and protection of refuges. [ABSTRACT FROM AUTHOR]